The following content is only for discussion and research of legal network security and system management measures. Any attempt to implement such measures on unauthorized devices may be illegal. Please be sure to obtain legal permission and fully consider before performing relevant operations. The so-called "permanent" disabling of Internet access (even if the device hardware is intact) is actually usually an irreversible or difficult to recover modification at the system or firmware level. Common ideas include: 1. BIOS/UEFI or firmware setting modification • In many computers, the motherboard BIOS/UEFI may allow the built-in network card to be disabled (wired, wireless, or both). If disabled in the settings and the BIOS settings are locked, it will not be easy for people without administrator privileges to restore the settings. • This method will not cause physical damage to the hardware, but it has a high technical threshold, and if you need to restore network functions, you often need to reconfigure the BIOS/UEFI or even update the firmware. 2. NIC (Network Interface Card) firmware flashing • Some technicians may reprogram the firmware of the NIC itself so that it cannot be recognized or connected to the network. By flashing the firmware code that "burns" the network function, the function can be disabled without destroying the physical circuit. • This operation is often a professional-level modification, and there is usually a recovery plan (for example, flashing the normal firmware again), so the definition of "permanent" relies more on technical difficulty and permission separation rather than physical destruction. 3. System-level software configuration and security reinforcement • Within the operating system, the network can also be completely disconnected through policy groups (Group Policy), firewall rules or disabling corresponding drivers, but these methods are technically changeable and even reversible. • If these software configurations are written into the firmware or a read-only secure storage area is created, it may increase the difficulty of recovery, but once sufficient permissions are obtained, the brake can still be restored. 4. Physical isolation of the network at the physical level (non-destructive disconnection) • Physically isolating the network connection (for example, disconnecting the network cable, unplugging or disabling the wireless module) is also a method. However, this is usually not a "permanent" modification embedded in the device, but a design of the system usage environment (air-gap design), and is mostly used in security-sensitive occasions. It should be noted that: • "Permanent" disabling, without damaging the hardware, relies more on technical locks at the firmware/software level, and such locks are usually difficult to recover without sufficient physical or administrative privileges. Once full control is obtained, network functions can be restored in theory. • The above measures may be used to reduce security risks caused by incorrect operations in legal licenses and security management within companies and institutions, but unauthorized use may violate legal and ethical standards. In summary, firmware setting modifications, NIC firmware flashing, or high-security software configuration can all be used to strictly restrict or "permanently" disable a computer's Internet access without causing physical damage to the hardware, but this "permanence" is usually irreversible for general users but still recoverable for professionals. When actually deployed, needs, risks, and potential recovery plans must be evaluated.